Build thread: Estes Indicator +

Discussion in 'Low Power Rocketry (LPR)' started by shanejohnson2002, Feb 14, 2019.

Help Support The Rocketry Forum by donating:

  1. Feb 14, 2019 #1

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    Started this build thread since my new kit will be delivered on Tuesday. Now that I have a functioning camera again (phone was just replaced, and I was able to pry the Canon T6 back from my wife) I plan on documenting as many steps as I can.

    I picked the Indicator because it's not a super-complicated build, and when my wife saw it, even she said it looked awesome. It's definitely one of the nicer kits Estes has produced recently.

    I'm calling it the "Indicator +" because I'm modding it to use standard motors vs minis. I also plan on putting some over-engineering into it...TTW fins, ejection baffle, etc. Mostly for testing / learning new techniques, but also because those fins are quite large compared to the BT and I'd like to protect them as much as I can. Yeah, it's overkill...so sue me.

    I modeled it in OR with the new components, and it appears to be plenty stable even with the larger motors. The altitude range widens quite a bit too....from the 200ft advertised max to between 700-800 on C-size motors.

    List of goals:
    - Replace 2-piece fins with 1-piece tabbed fins. This will require building a single forward and rear fin, tracing them, and re-cutting them with added tabs on a new piece of balsa / basswood / whatever.

    - Airfoil shaping and papering the fins properly.

    - Upgrade motor mount as previously described.

    - Take my time and try to nail the paint job. Looking at using Metallics / Pearls instead of gloss (or glitter this time...holy cow that's a mess). ESEPCAILLY around the fillets, since I've never painted fins with fillets a separate color. Measure, mask, re-measure, etc.

    Pictures starting Tuesday, comments/critiques welcome until then.
     
    Matt_The_RocketMan likes this.
  2. Feb 15, 2019 #2

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    It has begun!

    [​IMG]
     
  3. Feb 15, 2019 #3

    Matt_The_RocketMan

    Matt_The_RocketMan

    Matt_The_RocketMan

    Well-Known Member

    Joined:
    Feb 7, 2019
    Messages:
    396
    Likes Received:
    44
    Gender:
    Male
    Location:
    Houston TX
    So you are building [​IMG] is that correct?
    Or are you going rouge form the kit and making a larger version?
     
    shanejohnson2002 likes this.
  4. Feb 15, 2019 #4

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    nope that's the kit. just putting a bigger motor mount in, if I can.

    if not, no biggie.... just have to apply the ideas elsewhere. OR says it should work though, so im hoping.
     
  5. Feb 15, 2019 #5

    Matt_The_RocketMan

    Matt_The_RocketMan

    Matt_The_RocketMan

    Well-Known Member

    Joined:
    Feb 7, 2019
    Messages:
    396
    Likes Received:
    44
    Gender:
    Male
    Location:
    Houston TX
    You shouldnt have an issue in putting a large engine mount in it as long as the rocket has similar diamiter as the mounting circles.

    Also You are trying to out C or D or E engines in this rocket?
    C engines have same diameter as A and B class engines.
    If not you have done the right thing in buy those engine mounts
     
    shanejohnson2002 likes this.
  6. Feb 15, 2019 #6

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    Maxing out with Cs on this one.
     
  7. Feb 15, 2019 #7

    Matt_The_RocketMan

    Matt_The_RocketMan

    Matt_The_RocketMan

    Well-Known Member

    Joined:
    Feb 7, 2019
    Messages:
    396
    Likes Received:
    44
    Gender:
    Male
    Location:
    Houston TX
    So to answer the question:

    Length: 21.2 in. (53.8 cm)
    Diameter: .74 in. (19 mm) top / .98 in. (25 mm) bottom
    Estimated Weight: 1.3 oz (36.9 g)

    Laser cut wood fins, waterslide decals, 9 in. (22.9 cm) parachute recovery

    Projected Max Altitude - 200 ft. (69 m)

    Recommended Engines: A3-4T (First Launch), A10-3T

    So yes you did the correct thing, just make sure that your engine mount can actually fit inside of the body tube
     
  8. Feb 15, 2019 #8

    GlenP

    GlenP

    GlenP

    Well-Known Member

    Joined:
    Oct 4, 2014
    Messages:
    1,485
    Likes Received:
    111
    shanejohnson2002 likes this.
  9. Feb 15, 2019 #9

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    Sure did. That was sort of my inspiration...although I didn't want to go full 2-stage with this one. It's a very cool idea, and this design lends itself perfectly to it.

    I also think it could be cool to do 2 mini stages. Someone in that thread mentioned having a 2-stager that does full boost/sustain/recovery inside of 200ft. Pretty cool if it can be safely done.

    This is more a combo of beefing up, both motor and structure, and practicing skills like airfoil forming, papering, TTW fin design/mounting, etc. I'll post the OR file in a bit when I can get back to my computer.
     
  10. Feb 15, 2019 #10

    neil_w

    neil_w

    neil_w

    Number 1 Balsa Nerd TRF Supporter

    Joined:
    Jul 14, 2015
    Messages:
    5,256
    Likes Received:
    505
    Location:
    Northern NJ
    Great kit. Why would you want to make the fins one-piece? Leading strakes like that are virtually *always* added on as a second piece; there's no way to maintain strength of the whole thing with a single grain direction. True even if you paper them.
     
    shanejohnson2002 likes this.
  11. Feb 15, 2019 #11

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    OR screenshots shared. I'll figure out how to add the actual file later. Stability looks good with everything from A8 to C6...3.08 to 2.43 respectively, with everything else falling neatly in the middle. All of the flight profiles look comfortably straight as well.

    The alerts in the sims are from the body tube sizes changing.


    [​IMG]

    [​IMG]
     
  12. Feb 15, 2019 #12

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    Good point...I was wondering if it would make any difference. If I'm papering them anyway, I suppose it won't matter much....and it would save a step.
     
  13. Feb 15, 2019 #13

    Matt_The_RocketMan

    Matt_The_RocketMan

    Matt_The_RocketMan

    Well-Known Member

    Joined:
    Feb 7, 2019
    Messages:
    396
    Likes Received:
    44
    Gender:
    Male
    Location:
    Houston TX
    Still Waiting for Kit? I'm anxious how the build goes !
    Cheering you on and All the support in the world is with you!
     
  14. Feb 15, 2019 #14

    neil_w

    neil_w

    neil_w

    Number 1 Balsa Nerd TRF Supporter

    Joined:
    Jul 14, 2015
    Messages:
    5,256
    Likes Received:
    505
    Location:
    Northern NJ
    One quick addendum... the strength of the strake is not really very important after it is glued down, since it has no way to really flex. But you may find it to be *incredibly* delicate until it's papered and/or glued. If you plan on rounding the leading edge it could be very difficult without breaking it. That is based on my experience anyway.
     
    shanejohnson2002 likes this.
  15. Feb 15, 2019 #15

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    Still waiting...but there's good news. It'll be here tomorrow instead of Tuesday.

    Also decided to ditch the retainer ring I included to grip the front edge of the forward fins' tabs...I'll just use the baffle instead. The difference in the locations of the CG / CP between the two designs is minimal...stability is still just over 2.

    I did pick up all but the red paint for this build today...I can post pics of that in a bit. Rustoleum filler/primer, Black Night metallic, Pearl Mist metallic, and another can of Gloss Clear enamel. Also 6 packs of sandpaper, grades 400 - 3000.

    This forum is pretty darn supportive. I have no doubt I'll make a litany of mistakes on this build, but I hope to apply some lessons learned from my first (the Crossfire ISX).
     
  16. Feb 15, 2019 #16

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male

    I will always defer to experience. So basically I should at least glue it to the main fin before I worry about rounding it?

    While we're discussing fins...how would you (or anyone else) suggest I deal with papering the leading edges with that angle the strake makes with the fin? I suppose I could just leave the fins squared and take the easy way out, with one solid piece of paper on each side....but that's no fun.
     
  17. Feb 15, 2019 #17

    Matt_The_RocketMan

    Matt_The_RocketMan

    Matt_The_RocketMan

    Well-Known Member

    Joined:
    Feb 7, 2019
    Messages:
    396
    Likes Received:
    44
    Gender:
    Male
    Location:
    Houston TX
    With guys whom have built skill Level 4 builds the details are the best part of the build, but don't forget if you build the rocket correctly first off.
     
  18. Feb 15, 2019 #18

    Matt_The_RocketMan

    Matt_The_RocketMan

    Matt_The_RocketMan

    Well-Known Member

    Joined:
    Feb 7, 2019
    Messages:
    396
    Likes Received:
    44
    Gender:
    Male
    Location:
    Houston TX
    Also before you do a colored paint job always always make sure to put the primer coat on smoothly and allow to dry, and also when you put waterside details on make sure you put a clear coat to make sure the seal keeps them on there! Best of Luck
     
  19. Feb 15, 2019 #19

    Wallace

    Wallace

    Wallace

    Well-Known Member

    Joined:
    Feb 16, 2017
    Messages:
    1,224
    Likes Received:
    203
    Paper the entire fin, harden the edges with CA and sand your profile. Not sure if it's right or wrong but it's worked for me.
     
    shanejohnson2002 likes this.
  20. Feb 16, 2019 #20

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    Kit is here! Pictures tonight.

    Also thinking about the fins...I'm thinking I'll profile the trailing edges, paper, secure edges with CA, and then round the front (and probably re-apply some CA if needed). I'm not sure how else to tackle that reverse sweep with the strake.
     
  21. Feb 17, 2019 #21

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    So, progress on first night of building:

    [​IMG]

    - tubes marked for slots and lugs
    - fins glued, sans tabs.
    - nosecone glued
    - 18mm motor mount built.

    I have a plan of attack for airfoiling these fins, but I'm having second thoughts. it's not really necessary on a rocket this small / light...and the extra work isn't really worth the trade off of a few feet of altitude. Which im getting more of anyway due to the motor upsizing. We'll see. I'll try it on scrap first, of course, before any decision is made.

    Awaiting more 3/32 balsa to make my tabs. Looks like I'll be making a trip to the craft store Monday.
     
  22. Feb 17, 2019 #22

    Rex R

    Rex R

    Rex R

    LV2

    Joined:
    Apr 21, 2010
    Messages:
    6,027
    Likes Received:
    116
    I'm thinking that some 1/8" square stock glued lengthwise between the centering rings of the motor mount(and a smidge of sanding) ought to work a treat to add strength w/o a major weight hit.
    Rex
     
    shanejohnson2002 likes this.
  23. Feb 17, 2019 #23

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    yep. The OR plan shows pretty much exactly that, only it's 3/32" thickness to match the stock fins. it ends up being 1-1/2 inches long, and off the top of my head, about 1/8" tall, because that's the distance between the centering rings on the motor mount. That should actually make them slightly oversized, which is fine.
     
  24. Feb 17, 2019 #24

    GlenP

    GlenP

    GlenP

    Well-Known Member

    Joined:
    Oct 4, 2014
    Messages:
    1,485
    Likes Received:
    111
    If you launch that on a C up to 1000' you might want to cut a hole in the chute, or swap in a streamer, if you are on a smaller field. The fin design is such that the engine should hit the ground first and can probably survive a good hard landing. The fins and strakes look like they go all the way up to the transition shoulder, so the lower body tube probably won't have a weak spot at the fin root/leading edge point just in front of the engine mount tube to buckle on you either.
     
    shanejohnson2002 likes this.
  25. Feb 17, 2019 #25

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    Not planning on launching a C for a while...but as a general rule I cut holes in my chutes. The strakes just miss the transition shoulder by 1/8" or so, but they do cover the inner portion of it. I think, once glued up and filleted, it should be plenty strong, especially with tabbed TTW papered fins. That said, I agree about the streamer. I attach my chutes with fishing swivels so it's pretty easily swapped out for a streamer later on.

    I'm not trying to make it bulletproof, but I do want to take my time and make something that will last a good while.
     
  26. Feb 18, 2019 #26

    neil_w

    neil_w

    neil_w

    Number 1 Balsa Nerd TRF Supporter

    Joined:
    Jul 14, 2015
    Messages:
    5,256
    Likes Received:
    505
    Location:
    Northern NJ
    Wait, you're gonna glue the tabs onto the fins? I'm not sure if that actually accomplishes anything. Normally the tabs would be part of the fin. I'll let others chime in whether this is worth doing.
     
    shanejohnson2002 likes this.
  27. Feb 18, 2019 #27

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    Well, worth doing or not, it's done. I considered that the tab/ fin joint would be the weak spot, but reinforcing with paper *should* help some. I hope. If not, you'll be seeing an "Indicator + build thread, second attempt" soon lol.
    [​IMG]
     
  28. Feb 18, 2019 #28

    Rex R

    Rex R

    Rex R

    LV2

    Joined:
    Apr 21, 2010
    Messages:
    6,027
    Likes Received:
    116
    the confusion no doubt stems from the fact that usually the fin tab grain matches that of the fins (for direction) :). and I was picturing the body tube as being non slotted...well if nothing else this will be a learning experience. would suggest that care be taken to avoid the motor hook interfering with the fins.
    Rex
     
    shanejohnson2002 likes this.
  29. Feb 18, 2019 #29

    GlenP

    GlenP

    GlenP

    Well-Known Member

    Joined:
    Oct 4, 2014
    Messages:
    1,485
    Likes Received:
    111
    Wood glue is stronger than the wood. So, the joints will actually be the strongest part, and the way you have cut the grain on the tabs make them the weakest link themselves.

    Those fins will probably never hit the ground so you should be okay, but if they were aft swept and did hit ground on a hard landing, the fins could pop off entirely with the tabs splitting right down the middle. You will have a very strong glue joint to the engine mount, and a very strong joint to the fin, but the tab itself has the grain going in the wrong direction. Papering them might help a little. I think you are probably okay due to the forward swept shape of the fin making them very less likely to hit the ground first on landing.
     
    shanejohnson2002 likes this.
  30. Feb 18, 2019 #30

    shanejohnson2002

    shanejohnson2002

    shanejohnson2002

    Well-Known Member

    Joined:
    Feb 6, 2019
    Messages:
    103
    Likes Received:
    19
    Gender:
    Male
    Good news:

    Kids went to bed early tonight (out of character, but I'm not complaining)....so I soldiered on. I ended up rounding the leading and trailing edges, as my airfoil jig didn't work to my satisfaction. I probably just need practice, but whatever. Rounding is fine for this build.

    So, tonight:

    [​IMG]

    - Aft fins shaped, edges CA'd and papered. The fins are *considerably* stronger when papered...the flex you normally feel in 1/16" balsa (which, btw, I believe this is indeed 1/16 and not 3/32) is almost completely gone. Also discovered that you can still round the fin edges after papering. I think the combination of the wood glue and the paper makes for a pretty strong "composite" fin structure.

    I honestly haven't given any thought to the grain of the tabs (obviously lol). Another one to add to the notebook of "things not to do". I think the paper made it strong enough though, and considering I'll be adding fillets as well, it should be structurally pretty sound.

    - Fin Jig made from Payloadbay.com. Printed out the .pdf, spray-glued it to some foam board, and cut it out. Works better than the Estes plastic fin jig by a mile, at 1/10th the total cost. I also made a BT-20 version for the forward fins. I numbered each fin to correspond with each slot in the tube, shaped/cut/sanded it to fit, and stuck it on.

    After securing the aft end in the jig, I noticed the strake on my #1 fin is a little skewed. Not bad, but it will need to be straightened after everything dries. The good news is I have only applied glue to the tabs and the aft ends, and a VERY small (like, toothpick-tip-sized) drop of CA to "tack-weld" the tips of the strakes in place. No biggie...it should cut loose pretty easily tomorrow for a bit of in-situ straightening (i.e., holding a ruler against it while I re-tack it in place).

    Short of gluing on the launch lugs, there's not much else I can do to the back end before painting. I ordered a BT20 baffle so when it comes in, I can continue the forward half.

    Also tested some paint. I'd really like to try Duplicolor Metalcast for the fins and nosecone, but it's twice what Rustoleum costs, and I already have the appropriate colors on-hand. Rustoleum colored metallics (i.e., not gold/silver...I'm using red and black) are more like a fine metal flake, and less of a shiny anodized effect. I may try Metalcast yet if I can get some soon enough, but we'll see.
     
    Last edited: Feb 18, 2019

Share This Page